Construction of hot blast stoves



H. A. BRASSERT 1,315,900-

CONSTRUCTION OF HOT BLAST STOVES July 28,1931.

2 Sheets-Sheet 1 v 6 mv y iv e j Filed June 19, 1930 I fizz/6%:

H. A. BRASSERT CONSTRUCTION OF HOT BLAS'T STOVES July 28, 1931.

Filed June 19, 19 so 2 Sheets+Sheet 2 Patented- July 28,: I i

IIERMAN A4 rAuYQor' Go, Iruifriiois,

BRAssEBr; or oi-ironed inLINo s, ASSIGNOR TO K. A. 'BRAssnR'r a'fooiu I A", CORPORATION or ILLINOIS l ooirs'rituo riou or nor istssr s'roves "Application filed'eJ'un'e 1 9,

I I invention relatefs'to the construction 1 "hotrblast stoves-for heating the blast air used in the v operation yof. blast i furnaces and has for its special; purpose the protectionof the h'ottestf zone ofthei regenerative;checkerwork from destruction: by excessive temperatures."

7 1Through the recently developed use 7 of. -e Washed gas which contains a verylow per-;

'centaige of moisture compared to the gas previously used and the use of more "elficient burners, thetemperatures in the top section of jthecheckerwork have; been materially raisedlresulting inthesoftening and eventual I collapseofthispart of the 'checker-structure,-

Whichup tojthisjtinie has been made of the sarne material as the rest of the checkers, x

Heretofore the brickwork ofthecombus 7 tion chamber :anClfiGhCkeIWOIk in stoves has 7 consisted Of' th Q'llSua/l qualities' of No 1 fire sac brick made of fire" clay-containing a mixture of silica and alumina in proportions of'about 1 1A partsof silicato oneI-part ofalumina; In some case's No; 2 quality hasbeen used in the lower sections-of the stove Where high temperatures areinot encountered. I The No. l clay fire brick-endure temperatures up :to

2200" Y jF, Without gradually s'oitening. Untilnow-there: has been no: need for the ,fuse ,oi materialhavingahigher softeningtpointv than thatofjhigh grade No; 1 'firey brick.

Silica, alumina and magnesiteibrick which can resist higher temperatureshave not been I used onaccount of their-additional-cost and onpaccount Of thQII GXPaIISlOII ooefliclent Stoves being at considerable variance with thatof fire clay'brick. v

'been' I I developed 7 which; by means of checker fillers in succes-- -sive;stages,- control the velocitiesof gas and air, thus equalizing the temperature I ranges in the checkerwork during aicycle to afar greater extent than was ever'acco nplished before; [All of the zones of'thejcheckerb-rick are subjected toja smaller variation in temperature upon reversal of the stove than heretofore. In other Words, thejtempera tures fgradient'is more uniform" at any one zone but it extends to a higher temperature "and also a lower temperature as'between the top and the bottom because the entire stove 1530. Serial No. 462,219.

is doing asubstantially uniform amount of ork, The result ofthis,asthe'top zone is concerned, is that'the ascending cold: blast has been heated so high before it'enters "1 r thetop z one that it dbesnotcool oil the top zone sufficiently to'cause any serious contrac-v t'ionof the brick Work. On the other hand, when the stoveis reversed on account-of the top zonerernaining hot during'the air blast '60 period, the'difierence in temperature'hetween the gases of-combustionascendingthe combustion chamber and striking the top zoneof the checkerwork and thecheckerbrick is 1 u again not sufficient to cause undue expan-. sion. f Therefore, the applicationof brick havine a higher 1 fusion point and a higher or difierent 1 expansion 1 coefficient from the rest of the. fire lorik use d in thelvvalls of the stove and in the checkers below is not objectionable and I havediscovered that the use of such brickis now practical and econornical. p I

A .furtherfeature ofmy invent on cons sts dust is acid in character I prefer to'use silica brick; ifit is alkaline in character Iprefer to use magnesite brick; and if it isneutral in character I prefer to use alumina brick; It? will be understoodthat my invention in} cludes theuse of brick made of any material having a highersoftening point thanistandi ard No. 1 fire brick, such softening point he ing high' enough to sustain the heat present in theupperportion of the type of stoves referred toabove'.

, It is an object of thepresent.inventiou to" provide a new and improved stove construe-i i j tion in which the brickwork at the hottest zone of theregenerative cheokerwork is of a [Itis anadditional object to provide aton structionof this character in which the char-o character to" resist softening at the highest 1 temperatures prevalent at this-point.

acteristics of the brick used at the high temperature-points are selected in relation to the character of the remaining dust content of the gases used for combustion in the stove. It is an additional object to provide a construction whichzma-y be applied to existing stoves without material alteration therein.

Other and further'objects will appear as V tol high temperatures, but these wallslose thedescription proceeds.--

I have illustrated in the accompanyin drawings, one embodiment of the type of stove in Connection with which my, invention is particularly adapted foruse.

In'the drawings Figure 1'is a' fragmentary plan .portio'n of the stove;

View of a 1Figure2 is a fragmentary View on an en of an..1nter-- I g V struction shown and descr bed 1s llustrative larged :scale showing a section mediateportion ofthe stove; 'Figure'3 is a'viewsimilar to Figure 2, but

showing a lower portio'n'of the stove; Figure A isa fragmentaryfview showing the supporting construction; and

' Figure 5 is aschematic vertical elevation showing diiferent'types of brick .in', difi'erent verticalsections offthe stove. g

Inthe drawings, the walls of the combus 'ti'on chamber are indicated at 11, the outer stove wall at. 12, and the'maincheckerbrick at 13.

tagonal in form and have a substantially square passageway 14 extendingvertically through the brick.- Thebrick are so placed as 'to'tormyertical passageways 15 between them, these passageways being similar in form and design'to'the passageways 14 These brick 1 3 are so placed that each horizontal layer breaks oint with the horizontal layers A above and below.if'Thustheverticalpassages through the brick also extend in alternate layers between brick. v.

As shown in Figure 5,"theupper portion of the checkerwork may consist merely of the main-checkerbri'ck 13. 1 An intermediate sec tion may consistof the checkerbrick' 13-to-' gether with' filler brick 16,"jsomej1of which may be 'aplaced-at-jright angles to each other;

as shownfin the drawings] A lower section may consist of thebrick 13 and enlarged filler. brick 1-' 7, s'hown"in Figure'2 and Figure 5,

and-astill lower section may include the checkerbrick 13 and 'sti'll larger filler brick bottom construction may include supporting brlck 19 and special metal meme ber'sQO which latter extend [across the me.

cal passages and serve to support the filler brick The details of constructionof the checkerwork' sho n form no: part of my invention Q and need -not bef further, discussed.

The stove construction shown is oneform in "'which' the effective passageway for the" gases andair*isfprogressively reduced tow ard'the bottomof the stove'sothat the tem- These .main checkerbrick are generally 00- r of thecheckerwork.

someof their heat which passes into the surrounding checkerwork while the uppermost checkerbrick"areflcompletely surrounded by :other brick and thus reach a higher temperonly and that I contemplate such changes and modifications as come "within the spirit and scope of the appended claims.

' Iclaim: 1 j 1. In ahot blaststove'for the heatingof air, said'stove being heated by the combus tionofa I gas having a dust content, a regenerative checkerwork construction having progressively reduced effective passage areas in the lower portions thereof, said construc-' ion comprising standard fire'brick in the lower portion of the stove and higher temperature resistant refractory brickin the up]- per portion of theystove, said refractory brick conforming in character to the'dust content of the gas used for'combustion. t i

2. In 7 a'hot, blast stove, a regenerator' h'aving progressively. reduced efi'ective passage areas in the lower portions thereof, said construction comprising standard firebrick in V the lower and middle portion of the checker 105 column and higher temperature resistant brick in the upper portion of the c'he'ckercolunin, said higher refractory materialhaving a materially higheralumina content than the standard fire brick used in the lower parts r 3. In a hot blast stove,' a regeneratOr havng. progressively reduced efiective passage areas in the lower portions thereof; saidcon-t struction comprising standard firebrick in the lower and middle portion ofthe checker column and higher. temperature resistant brick in the upper'portion of the checker column, said higher refractory material con-' taining more'than 95% silica." I

Signed atYChiC agO, Illinois, this 14th day ofJune, 1930. I a I HERMAN A; BRASSERT' 

